Roewer, U. (2008). Environmental Protection Expenditure by Industry in the European Union 1997-2004. Statistic in focus: Environment and energy.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रRoewer, Ute. "Environmental Protection Expenditure by Industry in the European Union 1997-2004." Statistic in Focus: Environment and Energy 2008.
एमएलए (8वां संस्करण) प्रशस्ति पत्रRoewer, Ute. "Environmental Protection Expenditure by Industry in the European Union 1997-2004." Statistic in Focus: Environment and Energy, 2008.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.